This is a grim tale. A man almost lost the use of his right hand, and did suffer terrible injuries to his fingers. All because he picked the wrong bottle of powder off the shelf.
Similar Labels, Disasterous Consequences
The shooter, Denny K., was assembling some rounds for his brand new 7mm-08 Savage hunting rifle. He thought he was loading with Hodgdon Varget. Instead he had filled his powder measure with Hodgdon TiteGroup, a fast-burning pistol powder. The labels are similar, so the mistake is understandable. But the results were devastating. Here’s what 41 grains of TiteGroup can do in a 7mm-08:
Posting on the Firing Line, in a thread entitled “Lucky to Be Alive”, Denny writes:
“This is the hardest post to post. I know if I had read it a week ago my comment would have been: ‘You have no business reloading’. I had everything perfect, except pouring the wrong powder in the powder measure. I type this slowly with my left hand, embarrassed but … possibly saving someone else a tragedy or, like me, a long drive to the Emergency Room and surgery to save my finger.”
The Still-Sealed Bottle of Varget
Denny did not initially comprehend exactly why the kaboom happened. He thought maybe his new Savage rifle was at fault. Then, on his return home, he discovered something…
Denny wrote: “The seven-hour period it took to go to ER, transport to Trauma Center and surgery made me think it was a Savage rifle issue. Brand new rifle, new brass, triple-checked loading data. The next day I was humbled when I realized the Varget powder was still sealed.
I knew what powder to use. I thought [Varget] was what I used. Not until the following day did I realize the Varget was still sealed.”
At that point, Denny realized what caused the accident — “operator error”. He knew he had to warn others about using the wrong powder: “I knew I needed to share my mistake, even though it is embarrassing, just to remind people. I’ve been reloading for 30 years…”
Editor’s Comment: Denny was not a novice reloader. His experience demonstrates that this kind of mistake can be made by any hand-loader, even one with decades of experience. Be safe guys, take your time when you load your ammo. Remove powders from measures after your loading sessions (pistol powders can look very similar to rifle powders). And by all means CHECK the LABEL on the jug. As the TiteGroup label says: “A little goes a long way.”
It’s not a bad idea to separate your pistol powders from your rifle powders, or perhaps even load for pistol in a separate part of your workshop.
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At the request of our readers, we provide select “Deals of the Week”. Every Monday morning we offer our Bargain selections. Here are some of the best deals on firearms, hardware, reloading components, and shooting accessories. Be aware that sale prices are subject to change, and once clearance inventory is sold, it’s gone for good. You snooze you lose.
1. Natchez — Special 5 Reloading Press Kit, $199.99
This is an excellent entry-level reloading kit, which is on sale for $199.99 at Natchez Shooters Supply. We like the relatively compact Special 5 press for most reloading duties. Eventually you many want to add an additional large heavy press, but this will get the job done. This kit includes an RCBS Powder Measure, Digital Scale, Powder Trickler, Hand Priming Tool, Load Manual, Loading Tray, and more. It’s hard to beat this combination of tools for under $200.00.
2. CDNN Sports — Remington 597 for $149.99
Looking for a “first rifle” for a family member? Consider this semi-auto Remington 597. It currently retails for just $149.99. That’s right, for under $150 you can get a reliable, self-feeding rimfire rifle that will provide years of fun for a young shooter. The 597 has a stock that’s sized right for both youngsters and adults. Receivers are dovetailed for standard rimfire rings and are also drilled and tapped to allow mounting of Weaver-style bases.
3. Grafs.com — Forster Co-Ax Reloading Press on SALE
If you’ve been patiently waiting to acquire a Forster Co-Ax® reloading press, now’s the time to strike. Grafs.com has Co-Ax presses on sale this week at $289.99. That includes shipping charges (with one flat $7.95 handling charge per order).
4. Grafs.com — NEW Nikon Wind Meter for SmartPhones, $28.99
Here’s a great new gadget for under $30.00. Nikon’s new Spot On™ Ballistic Wind Meter plugs directly into the headphone port on most popular smart phones. The Spot On Wind Meter reads both wind speed and direction and inputs the data directly into Nikon’s free Spot On Ballistics Mobile App (available for iOS and Android). This allows you to quickly determine and calculate wind drift corrections without needing a separate, dedicated wind meter. When not in use, the Nikon device easily fits in a pocket.
Everyone needs a good .22 LR rimfire handgun, and the Browning Buck Mark is a classic. This stainless, bull barrel version is marked down this week to $379.99. That’s a very good price. Buckmarks, with their excellent triggers and great ergonomics, are fun to shoot and VERY accurate. This is a pistol you can keep for a life-time and pass on to your kids. Browning says: “Every Buck Mark starts out as a solid piece of aircraft-grade 7075 aluminum alloy, and then is CNC machined to exacting tolerances. The crisp single-action trigger, hand reamed chamber, target crowned barrel and finely adjustable target sights mean the Buck Mark comes ready for fun straight from the box.”
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Will you be heading to the varmint fields this summer? Proper planning is key to a safe, satisfying, and productive varmint holiday. Of course you’ll be busy reloading, but you should make a check-list of all the gear and supplies you need. Bring a variety of rifles if possible — you’ll need to switch off as one barrel gets hot, and the chambering that works best for your close shots may not be ideal for those longer shots out past 400 yards. Here are some tips from our Forum members that can help you shoot more effectively, and avoid problems on your varmint hunt. Here’s one key tip: at your shooting station, put a strip of surveyor’s tape on a tall stake to show the wind direction. Then shoot in the direction the wind blows. This will minimize the effect of cross-winds.
From PatchHound: “The gear you bring will make or break a trip out to Prairie Dog land. A lot has to do with where you going and how far you are from [civilization]. For starters, bring lots of water. It will be hot in Wyoming in a few more weeks but it don’t hurt to bring warm clothes in case it snows. It’s best to wear leather boots unless you’re real good at dodging cactus while walking around. Good sunsceen will save the day too. [What you need to bring] really depends on whether you’re shooting on some friendly ranch or 100 miles in the middle of [a wilderness area]. Good survival gear is a good thing to have for the latter!”
From Stoner25mkiv: “I’d suggest an adjustable bipod if you are going to do any walking. A laser rangefinder is a huge asset. Have a fanny pack or backpack for extra ammo, water, bore-snake, etc. when you go on your walkabouts. We also take a couple pivoting benches, heavy movers’ pad/blanket, sandbags (Uncle Bud’s Bulls Bag) for shooting from near the vehicle. Boonie hat for blocking the sun, sun glasses, sunscreen. High leather boots.
Anyway, on to the rifles…consider bringing a 17 HMR, .223 Ackley bolt gun, .223 Ackley AR, and a 243 WSSM. Some years the 17 HMR isn’t removed from its case. We had a couple windless days and the 17 was lots of fun. I’d walk into the dogtown and then lay down and wait. After five minutes or so I’d have dogs within easy rimfire range, and out to as far as I’d care to stretch the rimfire. 275 yards was about it.”
From CTShooter: “The .204 [Ruger] is a laser beam and good to 400 yards easy. Forget the rimfire! Do you have a portable bench that pivots? Bring bipod, binocs. Bring a LOT of water. I have a milspec sniper shooter’s mat/drag bag with shoulder straps. It is good to carry everything when you want to wander off and shoot prone with bipod. Here’s a view through my 6BR in ND.”
From RJinTexas: “In most of the locations that we’ll be shooting we’ll usually set up a minimum of 200 yards from the edge of a major dog town. We’ll start by working over the close-in dogs and shooting our way out, some of these towns may run in excess of 500/600 yards deep. I believe that a rimfire will put you at a distinct disadvantage. The only rimfire that will somewhat work is the 17 HMR and you can reload for your 204s for close to the cost of HMR ammo and you’ll be less apt to be under-gunned. Your 204 will work well out to 300/400 yards unless the wind is blowing hard. We classify a 10-mph crosswind as a very calm day and what makes it a little more challenging is that it is usually also gusting. I only took my 17 HMR once, I’ve since even quit taking my 17 Mach IV because when the wind blows hard it range is limited to around 200 yards. Gusting wind will play havoc with 25gr pills.”
From Wes (P1ZombieKiller): “[For my first PD trip] there are so many things I was not ready for. The one thing that I did bring (that no one told me about) was a canopy. I’m glad I did. Even though the weather was [near perfect], I know that sun can humble you real fast. With my pop-up canopy, I could shoot all day without getting killed by the sun. You had to tie the canopy down real well or the wind would blow it across the pasture.
We sat on shooting benches that pivot 360°, and are fast and easy to set up. Most all shots were 175-250 yards. I just felt comfortable at that range. It was more fun for me to be able to film the hits, and the camcorder I was using just did not get good video past 350 yards. The digital zoom distorted the image too much. I knew I would only get this one chance to film my first P-dog outing, and I wanted to get it on film for [posterity].” To learn more about P1’s first Prairie Dog Trip, visit his Website.
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In this video, Forum member Erik Cortina shows how to create a custom modified case for use with the Hornady Lock-N-Load Overall Length Gauge (formerly the Stoney Point Tool). While Hornady sells modified cases for many standard cartridges, if you shoot a wildcat such as the 6mm Dasher or .284 Shehane, you’ll need to create a custom modified case*. And even if you shoot a standard cartridge such as the .308 Winchester you can get more consistent measurements if you make a custom modified case from a piece of brass fired in your chamber.
The process is straight-forward. Take a piece of brass fired in your chamber and full-length size it (with about .002″ shoulder bump). Then you need to drill out the primer pocket. Erik uses a mini-lathe for the operation, but this general process can be done with a drill press or other tools. Erik shows how to do this with a 0.290″ HSS (High Speed Steel) drill bit on a mini-lathe. After drilling the hole comes the tricky part — you need to tap the case with the precise 5/16″ x 36 threads per inch (tpi) right-hand thread that matches the male thread on the O.A.L. Gauge. This 5/16″ x 36 tpi tap is pretty uncommon, but you can order it from Amazon.com if you can’t source it locally.
If you use a mini-lathe, Erik suggests loosening the tailstock slightly, so it can float while cutting the threads. Erik also says: “Make sure you get the tap on pretty tight — it’s going to want to spin.” Erik turns the case at about 100 rpm when tapping the threads. Once the case and tap are rigged, the actual tapping process (see video at 6:00) takes only a few seconds. While the mini-lathe makes the tapping process go more quickly, the threading can also be done with other systems.
TIP: Don’t just make one modified case, make three. That gives you one for your range kit, one for your home reloading bench, plus a spare (since you WILL eventually lose or misplace one).
Here’s the Stuff You Need
5/16″-36 TPI Threading Tap
The required thread is somewhat uncommon. You need a 5/16″ – 36 tpi Right Hand Thread Tap. If you can’t find it locally, Amazon.com carries the correct tap. Erik notes: “The 5/16-36 tpi tap is not a common size. I think Hornady did this on purpose to make it more difficult for the average guy to make his own modified cases.”
0.290″ Drill Bit
Erik uses an 0.290″ HSS “L” drill bit. (This “L” Letter Gauge code designates a 0.290″ diameter bit). A close metric equivalent would be 7.3 mm (0.286″). Erik says: “A 9/32″ drill will also work but it will be harder to run the tap in since the hole will be .281″ instead of .290″ with the Letter Gauge L bit.”
Tips for Using O.A.L. Gauge with Modified Case
We’ve noticed that many folks have trouble getting reliable, consistent results when they first start using the Hornady O.A.L. Gauge (formerly the Stoney Point Tool). We’ve found this is usually because they don’t seat the modified case properly and because they don’t use a gentle, consistent method of advancing the bullet until it just kisses the lands.
Here is our suggested procedure for use the O.A.L. Gauge. Following this method we can typically make three of four measurements (with the same bullet), all within .001″ to .0015″. (Yes, we always measure multiple times.)
1. Clean your chamber so there is no build-up of carbon, debris, or lube. Pay particular attention to the shoulder area.
2. Screw the modified case on to the O.A.L. Gauge. Make sure it is seated firmly (and doesn’t spin loose). Note, you may have to re-tighten the modified case after insertion in the chamber.
3. Place your selected bullet so that the ogive (max bullet diameter) is behind the case mouth. This prevents the bullet from “snagging” as you insert the tool in the action.
4. Insert the O.A.L. Gauge into your chamber smoothly. Push a little until you feel resistance. IMPORTANT — You need to ensure that the shoulder of the modified case is seated firmly against the front of your chamber. You may have to wiggle and twist the tool slightly. If you do not have the modified case seated all the way in, you will NOT get a valid measurement.
5. Advance the bullet slowly. (NOTE: This is the most important aspect for consistency!). Push the rod of the O.A.L. tool gently towards the chamber. DON’T shove it hard! Easy does it. Stop when you feel resistance.
6. IMPORTANT. After gently pushing on the rod, give the end of the rod a couple forward taps with your finger. If your bullet was slightly skewed, it may have stopped too far back. Adding a couple extra taps will fix that. If the bullet moves after the taps, then again push gently on the rod. NOT too much! You just want to push the bullet until it just “kisses” the lands and then stops. Do NOT jam the bullet into the rifling. If you do that you will never get consistent results from one measurement to the next.
* For a $15.00 fee, Hornady will make a custom modified case for you if you send two fired pieces of brass. Send fired cases and $15.00 check to: Hornady Manufacturing, Attn: Modified Cases, 108 S. Apollo St., Alda, NE 68810. More Info HERE.
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The USAMU recently published a “how-to” article about bullet sorting. While many of us may sort bullets by base-to-ogive length (and/or weight), the USAMU story explores the “how and why” of sorting bullets by Overall Length (OAL). Read the article highlights below, and make your own decision as to whether OAL sorting is worth the time and effort. Bryan Litz of Applied Ballistics says that sorting by OAL is not a bad idea, but base-to-ogive bullet sorting probably represents a better investment of your time.
Bullet Sorting by Overall Length
We’d like to share a specialized handloading technique which we’ve long found beneficial to our long-range (600 yards and beyond) accuracy. Sorting of bullets for extreme long range (LR) accuracy is not difficult to do, but some background in theory is needed.
Here at USAMU’s Handloading Shop, we only sort individual bullets for the most demanding Long-Range applications and important competitions. Only the most accurate rifles and shooters can fully exploit the benefits of this technique. The basic sorting process involves measuring the Overall Length (OAL) of the bullets, and grouping them in 0.001″ increments. It’s not unusual to find lots of match bullets that vary as much as 0.015″-0.020″ in length throughout the lot, although lots with much less variation are seen as well. Even in bullet lots with 0.015″ OAL variation, the bullet base-to-ogive length will show much less variation. Hence, our basic sort is by bullet OAL. One obvious benefit of sorting is easily seen in the attached photo. The few bullets that are VERY different from the average are culled out, reducing probable fliers.
How does one know what OAL increments to use when sorting? The answer is simple. As each lot of bullets is unique in its OAL distribution, it’s best to sample your bullet lot and see how they are distributed. In the attached photo, you will see a set of loading trays with a strip of masking tape running along the bottom. Each vertical row of holes is numbered in 0.001″ increments corresponding to the bullets’ OAL. A digital caliper makes this task much easier. As each bullet is measured, it is placed in the line of holes for its’ OAL, and gradually, a roughly bell-shaped curve begins to form.
Note that near the center, bullets are much more plentiful than near the edges. At the extreme edges, there are a few that differ markedly from the average, and these make great chronograph or sighting-in fodder. We recommend using a sample of 200 bullets from your lot, and 300 is even better. Some bullet lots are very consistent, with a tall, narrow band of highly-uniform bullets clustered together over just a few thousandths spread. Other lots will show a long, relatively flat curve (less uniform), and you may also see curves with 2 or more “spikes” separated by several 0.001″ OAL increments.
Bullet Sorting (OAL vs. Base-to-Ogive vs. Weight) — Litz Talks
I’m often asked what is a the best measure to sort bullets by, and the answer (to this and many other questions in ballistics) is: it depends.
Choosing to sort by overall length (OAL), base to ogive (BTO), bearing surface, weight, etc. can get overwhelming. Shooters typically look for something they can measure, which shows a variation and sort by that. It’s common for dimensional variations to correlate. For example, bullets which are longer in OAL are typically also shorter in BTO, and have longer noses. All these are symptoms of a bullet that was pushed a little further into the pointing die, or possibly had more than average lube while being swaged. So in essence, if you sort by BTO, you’re measuring one symptom which can indicate a pattern in the bullets shape.
So, the question still stands — what should you measure? You’ll always see more variation in OAL than BTO, so it’s easier to sort by OAL. But sometimes the bullet tips can be jagged and have small burrs which can be misleading. Measuring BTO will result in a lower spread, but is a more direct measure of bullet uniformity.
Then there’s the question of; how much variation is too much, or, how many bins should you sort into? Shooters who see 0.025” variation in BTO may choose to sort into 5 bins of 0.005”. But if you have only 0.005” variation in the box, you’ll still sort into 5 bins of 0.001”. What’s correct? You have to shoot to know. Live fire testing will answer more questions, and answer them more decisively than any amount of discussion on the subject. The test I recommend is to identify bullets on the extreme short end of the spectrum, and some on the extreme long end. Load at least 10 rounds of each, and take turns shooting 5-shot groups with them. If there is a difference, it will be evident. The results of the testing will answer your question of: should I sort based on X, Y, or Z?”
You can read more discussion on this and other similar subjects in the new Ballistics & Bullets board in the Accurateshooter.com forum. Heres a link to the thread which is discussing bullet sorting: Bullet Sorting Thread
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.009″ — The Record That Stood for 40 Years.
In 1973 Mac McMillan shot an amazing 100-yard, .009″ five-shot group in a benchrest match. The .009″ group was measured with a 60x microscope for verification. Mac McMillan shot the group using a handbuilt prototype McMillan rifle with an early McMillan stock.
Mac’s .009″ group was the “Holy Grail” of rifle accuracy. This .009″ record was considered by many to be unbreakable, a record that would “stand for all time”. Well, it took 40 years, but someone finally broke Mac’s record with an even smaller group. In 2013, Mike Stinnett shot a .0077″ five-shot group using a 30 Stewart, a .30 caliber wildcat based on the 6.5 Grendel. Stinnett’s .0077″ group now stands as the smallest 100-yard group ever shot in registered benchrest competition.* Read About .0077″ group HERE.
Stinnett’s success doesn’t diminish the significance of Mac McMillan’s .009″ group in the history of benchrest competition. For four decades Mac’s group stood as the ultimate standard of rifle accuracy*. For those of you who have never seen Mac McMillan’s .009″ group, here it is, along with the NBRSA World Record certificate. The target now hangs in the McMillan Family Museum.
*Somebody else might claim a smaller group, but unless moving backers or electronic targets were used, it cannot be verified. Moving target backers are used at registered benchrest matches to ensure that five (5) shots are actually fired in each group. That eliminates any doubt.
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In our Shooters’ Forum, there was an discussion about a range that was threatened with closure because rifle over-shoots were hitting a farm building over two miles from the firing line. One reader was skeptical of this, asking “how’s that possible — were these guys aiming at the stars?” Actually, you may be surprised. It doesn’t take much up-angle on a rifle to have a bullet land miles down-range. That’s why it’s so important that hunters and target shooters always orient their barrels in a safe direction (and angle). Shooters may not realize how much a small tilt of the barrel (above horizontal) can alter a bullet’s trajectory.
How many degrees of muzzle elevation do you think it would take to hit a barn at 3000 yards? Ten Degrees? Twenty Degrees? Actually the answer is much less — for a typical hunting cartridge, five to seven degrees of up-angle on the rifle is enough to create a trajectory that will have your bullet impacting at 3000 yards — that’s 1.7 miles away!
Five degrees isn’t much at all. Look at the diagram above. The angle actually displayed for the up-tilted rifle is a true 5.07 degrees (above horizontal). Using JBM Ballistics, we calculated 5.07° as the angle that would produce a 3000-yard impact with a 185gr .30-caliber bullet launched at 2850 fps MV. That would be a moderate “book load” for a .300 Win Mag deer rifle.
Here’s how we derived the angle value. Using Litz-derived BCs for a 185gr Berger Hunting VLD launched at 2850 fps, the drop at 3000 yards is 304.1 MOA (Minutes of Angle), assuming a 100-yard zero. This was calculated using a G7 BC with the JBM Ballistics Program. There are 60 MOA for each 1 degree of Angle. Thus, 304.1 MOA equals 5.068 degrees. So, that means that if you tilt up your muzzle just slightly over five degrees, your 185gr bullet (2850 fps MV) will impact 3000 yards down-range.
Figuring Trajectories with Different Bullets and MVs
If the bullet travels slower, or if you shoot a bullet with a lower BC, the angle elevation required for a 3000-yard impact goes up, but the principle is the same. Let’s say you have a 168gr HPBT MatchKing launched at 2750 fps MV from a .308 Winchester. (That’s a typical tactical load.) With a 100-yard zero, the total drop is 440.1 MOA, or 7.335 degrees. That’s more up-tilt than our example above, but seven degrees is still not that much, when you consider how a rifle might be handled during a negligent discharge. Think about a hunter getting into position for a prone shot. If careless, he could easily touch off the trigger with a muzzle up-angle of 10 degrees or more. Even when shooting from the bench, there is the possibility of discharging a rifle before the gun is leveled, sending the shot over the berm and, potentially, thousands of yards down-range.
Hopefully this article has shown folks that a very small amount of barrel elevation can make a huge difference in your bullet’s trajectory, and where it eventually lands. Nobody wants to put holes in a distant neighbor’s house, or worse yet, have the shot cause injury. Let’s go back to our original example of a 185gr bullet with a MV of 2850 fps. According to JBM, this projectile will still be traveling 687 fps at 3000 yards, with 193.7 ft/lbs of retained energy at that distance. That’s more than enough energy to be deadly.
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Here are some great rifle-centric landscape images courtesy of Nightforce Optics. Perhaps these “gunscapes” will encourage you to grab your rifle and head out into the woods this weekend. These images are part of an ongoing series of rifle photos posted on the Nightforce Facebook page. Can you identify the optics, and any of the locations? To see a full-screen version of each image, just click on any photo, and a larger version will load.
CLICK Any Image for Larger View
This is NOT a Photoshop job — that’s the actual view through a Nightforce scope of a deer. Photographer (and rifle-owner) Brandon F. says: “Ya’ll might enjoy this picture of a Fort Hood white tail… 400m away.”
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Sinclair International has created a series of instructional videos illustrating the basics of metallic cartridge reloading. The 8-part series starts with reloading basics and provides step-by-step, how-to instructions that will help new reloaders get started. Detailed, animated illustrations show you what happens inside the chamber when shooting, and inside the dies during each step of reloading. The videos can be viewed on Sinclair Int’l’s YouTube page. Shown below is the first video in the series:
Each of the eight videos is hosted by Sinclair Int’l President Bill Gravatt. Bill doesn’t just show you “how”, he tells you “why”. The how-to segments cover case inspection, proper die set up, case sizing, primer installation, powder measuring, bullet seating, crimping, and even goes into the record keeping needed for the handloader. “We wanted to give shooters who haven’t reloaded a look at all the advantages of creating your own ammo and how easy it is to get started,” said Gravatt, “without telling them they had to have any certain brand or type of equipment to do the job.” The eight videos are:
Part 1 — Intro to Video Series
Part 2 — Intro to Reloading Safety
Part 3 — Metallic Cartridge Components
Part 4 — The Firing Sequence
Part 5 — Tools for Reloading
Part 6 — Loading Bottle-Neck Cartridges
Part 7 — Loading Straight Wall Cartridges
Part 8 — Reloading Series Conclusion
Shown below is Part 5 of the video series, covering the tools used for precision reloading.
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Here is Ernie Bishop’s pride and joy, a specialty pistol nicknamed “Batman” because the black carbon-fiber stock looks like the Batmobile. This is one sophisticated handgun. Complete with scope, the Batman pistol weighs under 7.5 pounds, thanks to the ultra-light stock. The carbon stock is 6 inches wide at the fore-end, yet weighs just one pound. Ernie tells us: “This gun shoots amazing and is easy to shoot especially with my SEB MAX Rest.” Ernie adds, “The gun will soon also have a field-usable rear-grip stock so I can shoot it prone from a bipod as well.”
The Batman pistol is chambered for the 6mm “Long Dasher”, a 6mm 40°-shouldered variant of the 6.5×47 Lapua. Ernie loads Berger 105gr Hybrid bullets pushed by Hodgdon H-4350 powder.
The gun, crafted by Eric Wallance of Nawaka Firearms, features an XP-100 action, Jewell trigger, and 15″-long, Brux 1:8″-twist barrel with aluminum muzzle brake. Interestingly, this gun does not have a traditional recoil lug. Instead, gunsmith Wallace milled out a lug from the bottom of the XP-100 action to save weight. On top of the action, the rig carries a Sightron Inc S-III 6-24X56mm scope in Kelbly rings on a custom +20 MOA rail.
Long Dasher Wildcat
Shown at right is a “Long Dasher” 40° wildcat created by Forum member Sunbuilder. This is very similar to Ernie Bishop’s chambering, though there may be small variations related to reamer design (such as freebore). Sunbuilder’s 6-6.5×47 Improved (aka “Long Dasher”) reamer was made by Dave Kiff of Pacific, Tool & Gauge. This wildcat cartridge adds about 2.0 grains capacity to the 6.5×47 necked down to 6mm. The case certainly is impressive with that 40° shoulder. We’re just waiting for the tactical guys to starting run this improved cartridge with its original 6.5mm bore.
Here are three FIVE-shot groups at 500 yards, shot by Ernie’s Batman pistol:
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“The overturning moment MW tends to rotate the bullet about an axis, which goes through the CG (center of gravity) and which is perpendicular to the plane of drag….
Ruprecht Nennstiel, a forensic ballistics expert from Wiesbaden, Germany, has authored a great resource about bullet behavior in flight. Nennstiel’s comprehensive article, How Do Bullets Fly, explains all the forces which affect bullet flight including gravity, wind, gyroscopic effects, aerodynamic drag, and lift. Nennstiel even explains the rather arcane Magnus Force and Coriolis Effect which come into play at long ranges. Nennstiel’s remarkable resource contains many useful illustrations plus new experimental observations of bullets fired from small arms, both at short and at long ranges.
Shadowgraph of .308 Winchester Bullet
A convenient index is provided so you can study each particular force in sequence. Writing with clear, precise prose, Nennstiel explains each key factor that affects external ballistics. For starters, we all know that bullets spin when launched from a rifled barrel. But Nennstiel explains in greater detail how this spinning creates gyroscopic stability:
“The overturning moment MW tends to rotate the bullet about an axis, which goes through the CG (center of gravity) and which is perpendicular to the plane of drag, the plane, formed by the velocity vector ‘v’ and the longitudinal axis of the bullet. In the absence of spin, the yaw angle ‘δ’ would grow and the bullet would tumble.
If the bullet has sufficient spin, saying if it rotates fast enough about its axis of form, the gyroscopic effect takes place: the bullet’s longitudinal axis moves into the direction of the overturning moment, perpendicular to the plane of drag. This axis shift however alters the plane of drag, which then rotates about the velocity vector. This movement is called precession or slow mode oscillation.”
Raise Your Ballistic IQ
Though comprehensible to the average reader with some grounding in basic physics, Nennstiel’s work is really the equivalent of a Ph.D thesis in external ballistics. You could easily spend hours reading (and re-reading) all the primary material as well as the detailed FAQ section. But we think it’s worth plowing into How Do Bullets Fly from start to finish. We suggest you bookmark the page for future reference. You can also download the complete article for future reference and offline reading.
Some folks say you haven’t really mastered marksmanship unless you can hit a target when standing tall ‘on your own hind legs’. Of all the shooting positions, standing can be the most challenging because you have no horizontally-solid resting point for your forward arm/elbow. Here 10-time National High Power Champ Carl Bernosky explains how to make the standing shot.
Carl Bernosky is one of the greatest marksmen in history. A multi-time National High Power Champion, Carl has won ten (10) National High Power Championships in his storied shooting career, most recently in 2012. In this article, Carl provides step-by-step strategies to help High Power shooters improve their standing scores. When Carl talks about standing techniques, shooters should listen. Among his peers, Carl is regard as one of the best, if not the best standing shooter in the game today. Carl rarely puts pen to paper, but he was kind enough to share his techniques with AccurateShooter.com’s readers.
If you are position shooter, or aspire to be one some day, read this article word for word, and then read it again. We guarantee you’ll learn some techniques (and strategies) that can improve your shooting and boost your scores. This stuff is gold folks, read and learn…
How to Shoot Standing by Carl Bernosky
Shooting consistently good standing stages is a matter of getting rounds down range, with thoughtfully-executed goals. But first, your hold will determine the success you will have.
1. Your hold has to be 10 Ring to shoot 10s. This means that there should be a reasonable amount of time (enough to get a shot off) that your sights are within your best hold. No attention should be paid to the sights when they are not in the middle — that’s wasted energy. My best hold is within 5 seconds after I first look though my sights. I’m ready to shoot the shot at that time. If the gun doesn’t stop, I don’t shoot. I start over.
2. The shot has to be executed with the gun sitting still within your hold. If the gun is moving, it’s most likely moving out, and you’ve missed the best part of your hold.
3. Recognizing that the gun is sitting still and within your hold will initiate you firing the shot. Lots of dry fire or live fire training will help you acquire awareness of the gun sitting still. It’s not subconscious to me, but it’s close.
4. Don’t disturb the gun when you shoot the shot. That being said, I don’t believe in using ball or dummy rounds with the object of being surprised when the shot goes off. I consciously shoot every shot. Sometimes there is a mistake and I over-hold. But the more I train the less of these I get. If I get a dud round my gun will dip.* I don’t believe you can learn to ignore recoil. You must be consistent in your reaction to it.
5. Know your hold and shoot within it. The best part of my hold is about 4 inches. When I get things rolling, I recognize a still gun within my hold and execute the shot. I train to do this every shot. Close 10s are acceptable. Mid-ring 10s are not. If my hold was 8 inches I would train the same way. Shoot the shot when it is still within the hold, and accept the occasional 9. But don’t accept the shots out of the hold.
6. Practice makes perfect. The number of rounds you put down range matter. I shudder to think the amount of rounds I’ve fired standing in my life, and it still takes a month of shooting standing before Perry to be in my comfort zone. That month before Perry I shoot about 2000 rounds standing, 22 shots at a time. It peaks me at just about the right time.
This summarizes what I believe it takes to shoot good standing stages. I hope it provides some insight, understanding, and a roadmap to your own success shooting standing.
— Good Shooting, Carl
* This is very noticeable to me when shooting pistol. I can shoot bullet holes at 25 yards, but if I’ve miscounted the rounds I’ve fired out of my magazine, my pistol will dip noticeably. So do the pistols of the best pistol shooters I’ve watched and shot with. One might call this a “jerk”, I call it “controlled aggressive execution”, executed consistently.
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In our Shooters’ Forum, a member recently noted that he needed to pull down (disassemble) some ammunition that was loaded incorrectly by one of his shooting buddies. You can use an impact puller to do this task, but if you have more than a dozen rounds or so, you may prefer to use a collet-style bullet puller. These work very quickly and positively, making quick work of big jobs. The efficiency of the collet-style puller is worth the investment if you frequently disassemble ammo. These devices retail for under $25.00 (collets sold separately). Normally, you’ll need a specific collet for each bullet diameter. But collets are not that costly, so this isn’t a big deal, particularly if you only load a few calibers, such as .223, 6mm, and .308.
Hornady and RCBS use different mechanisms to tighten the collet around the bullet. On Hornady’s Cam-Lock Bullet Puller, a lever-arm on the top of the bullet puller serves to tighten the collet around the bullet. Simply rotate the lever from the vertical to the horizontal position to grab the bullet. Lower the ram to remove the case. The bullet will drop out when you return the lever arm to the vertical position. This is demonstrated in the video below:
Hornady Cam-Lock Bullet Puller Demonstrated
Collet bullet-pullers resemble a loading die with a lever or handle on the top. They screw into a standard reloading press. Hornady and RCBS both make collet-style bullet pullers. They use the same basic principle — the device tightens a collet around the bullet, and then the bullet is separated from the case by lowering the press ram. NOTE: Collet pullers may leave small marks on your bullets, unlike impact (kinetic) pullers.*
Like the Hornady tool, the RCBS Bullet Puller employs a collet to grab the bullet. However, the RCBS tool tightens the collet in a different way. The head of the RCBS tool is threaded internally. By rotating the lever arm clockwise in a horizontal circle you squeeze the collet around the bullet. To remove the bullet, after lowering the press ram, simply spin the lever arm back in the opposite direction. The use of the RCBS tool is demonstrated in this video:
RCBS Collet Bullet Puller Demonstrated:
WARNING: When removing bullets from loaded cartridges, always make sure there are no obsructions or debris in your shell-holder or under the loaded round. NEVER engage a primer seating accessory on your press when working with loaded rounds. You can cause a round to discharge by contacting the primer! Also, we recommend you keep your head and torso away from the bullet puller tool at all times.
*By contrast, impact pullers rarely mark bullets, particularly if you put a little bit of foam or paper wadding in the closed end of your impact puller. When dismantling loaded rounds, powder kernels can get trapped in the wadding, so you should remove and replace the wadding before changing to cartridges loaded with a different powder type (assuming you intend to save the powder).
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There is nothing more frustrating (or embarassing) than sending a live round into your expensive new chronograph. As the photo below demonstrates, with most types of chronographs (other than the barrel-hung Magnetospeed), you can fatally injure your expensive chrono if it is not positioned precisely.
When setting up a chrono, we always unload the rifle, remove the bolt and bore-sight to ensure that the path of the bullet is not too low. When bore-sighting visually, set up the rifle securely on the sandbags and look through the bore, breech to muzzle, lining up the barrel with your aim point on the target. Then (during an appropriate cease-fire), walk behind the chronograph. Looking straight back through the “V” formed by the sky-screens, you should be able to see light at the end of the barrel if the gun is positioned correctly. You can also use an in-chamber, laser bore-sighter to confirm the visual boresighting (see photo).
Adjust the height, angle and horizontal position of the chronograph so the bullet will pass through the middle of the “V” below the plastic diffusers, no less than 5″ above the light sensors. We put tape on the front sky-screen supports to make it easier to determine the right height over the light sensors.
Use a Test Backer to Confirm Your Bullet Trajectory
You can put tape on the support rods about 6″ up from the unit. This helps you judge the correct vertical height when setting up your rifle on the bags. Another trick is to hang a sheet of paper from the rear skyscreen and then use a laser boresighter to shine a dot on the paper (with the gun planted steady front and rear). This should give you a good idea (within an inch or so) of the bullet’s actual flight path through the “V” over the light sensors. Of course, when using a laser, never look directly at the laser! Instead shine the laser away from you and see where it appears on the paper.
Alignment of Chronograph Housing
Make sure the chrono housing is parallel to the path of the bullet. Don’t worry if the unit is not parallel to the ground surface. What you want is the bullet to pass over both front and rear sensors at the same height. Don’t try to set the chrono height in reference to the lens of your scope–as it sits 1″ to 2″ above your bore axis. To avoid muzzle blast interference, set your chronograph at least 10 feet from the end of the muzzle (or the distance recommended by the manufacturer).
Rifles with Elevated Iron Sights
All too often rookie AR15 shooters forget that AR sights are positioned roughly 2.4″ above the bore axis (at the top of the front sight blade). If you set your bullet pass-through point using your AR’s front sight, the bullet will actually be traveling 2.4″ lower as it goes through the chrono. That’s why we recommend bore-sighting and setting the bullet travel point about 5-8″ above the base of the sky-screen support shafts. (Or the vertical distance the chronograph maker otherwise recommends). NOTE: You can make the same mistake on a scoped rifle if the scope is set on very tall rings, so the center of the cross-hairs is much higher than the bore axis line.
TARGET AIM POINT: When doing chrono work, we suggest you shoot at a single aiming point no more than 2″ in diameter (on your target paper). Use that aiming point when aligning your chrono with your rifle’s bore. If you use a 2″ bright orange dot, you should be able to see that through the bore at 100 yards. Using a single 2″ target reduces the chance of a screen hit as you shift points of aim. If you shoot at multiple target dots, place them in a vertical line, and bore sight on the lowest dot. Always set your chron height to set safe clearance for the LOWEST target dot, and then work upwards only.
Other Chronograph Tips from Forum Members:
When using a chronograph, I put a strip of masking tape across the far end of the skyscreens about two-thirds of the way up. This gives me a good aiming or bore-sighting reference that’s well away from the pricey bits. I learned that one the hard way. — German Salazar
A very easy and simple tool to help you set up the chronograph is a simple piece of string! Set your gun (unloaded of course) on the rest and sight your target. Tie one end of the string to the rear scope ring or mount, then pull the string along the barrel to simulate the bullet path. With the string showing the bullet’s path, you can then easily set the chronograph’s placement left/right, and up/down. This will also let you set the chrono’s tilt angle and orientation so the sensors are correctly aligned with the bullet path. — Wayne Shaw
If shooting over a chrono from the prone position off a bipod or similar, beware of the muzzle sinking as recoil causes the front of the rifle to drop. I “killed” my first chronograph shooting off a gravel covered firing point where I’d not given enough clearance to start with and an inch or two drop in the muzzle caused a bullet to clip the housing. — Laurie Holland
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If you look at that 5-round group you might think it was shot with a 6 PPC or maybe a 6mmBR. But no, this was done with heavy 180gr Berger Hybrid bullets and the .284 Shehane, an improved version of the .284 Winchester. In fact, this impressive sub-quarter MOA group was shot while fire-forming with a very well-worn barrel!
Here’s a 5-shot 0.191″ group at 100 yards with my .284 Shehane fireforming loads. This barrel has 2200 rounds through it. It had 2000 as a straight .284 Win and then I set it back to .284 Shehane to form brass with. This was the first five rounds through it after I cleaned it after the last match. [The load was] 180 Hybrids with 54.0 grains of H4831 SC.
Ya, I figured why not I had some old barrels laying around so I just chopped 2″ off the back and 1″ off the front and chambered it up as a Shehane. Had 1000 pieces to fireform and didn’t want to do all that on a brand new barrel.
My fireform loads are going 2765 FPS. I have a 29″ barrel also though since it’s a setback. Once you get it formed I would push it faster than that or I wouldn’t even bother with the Shehane. My old straight .284 load at 2890 fps had ES spread in single digits for 10 shots. I figured if I get it up to 2935-2950 fps that will be a point or two saved in a several day match.
Fellow .284 Shehane shooter Erik Cortina notes that the .284 Shehane has a velocity edge over the straight .284 Win because it holds more powder: “The Shehane has more capacity than the .284 Winchester. Ryan is using 54.0 grains simply as a fire-forming load. Typical load for a Shehane is around 57.0 grains of Hodgdon H4831 SC.” By blowing the sidewalls out 0.010″, the .284 Shehane picks up about 3.3 grains of extra case capacity. That enhancement makes a BIG difference. The extra boiler room is enough to drive the 180s at 2900-2950 fps with H4831sc, with long barrels.
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At the request of our readers, we provide select “Deals of the Week”. Every Monday morning we offer our Bargain selections. Here are some of the best deals on firearms, hardware, reloading components, and shooting accessories. Be aware that sale prices are subject to change, and once clearance inventory is sold, it’s gone for good. You snooze you lose.
1. Stocky’s Stocks — Composite Stock with Bedding Block
Here’s a killer deal on a versatile Stocky’s Long Range Stock with aluminum V-block bedding system. For just $199.99, order this for Rem/Rem Clone long actions or short actions, with either narrow or wide (varmint/tactical) barrel channel. This would be a good choice for a varmint rifle. This is also offered with a matte black, tan, or olive baked-on textured finish for $229.97.
2. RCBS — Buy Green, Get Green Rebate
RCBS is running a very attractive Rebate Program currently. If you spend $300.00 on qualifying products you get a $75.00 rebate. Spend $50 and get a $10.00 Rebate. This program is limited to one (1) rebate redemption per calendar year, with a maximum of $75.00. CLICK HERE for more information. NOTE: To qualify, you must supply completed RCBS rebate coupon, original UPC barcodes from package, and original cash register receipt and/or dated, itemized sales invoice.
3. Midsouth — Nosler .308 Match Monster Bullets, $119.99 for 500
Looking for high-quality, name-brand .308-caliber bullets? You won’t beat the price on these Nosler bullets from Midsouth Shooters Supply. Five options are offered: 155 grain, 168 grain, 168 grain (with cannelure), 170 grain, and 190 grain. The 155s and 168s are just $119.99 for FIVE HUNDRED bullets. The 170s cost $131.28/500 while the big 190s cost $137.74/500. Those are insanely good prices, any way you cut it. The price on the 168s works out to just $23.99 per hundred. You could easily pay $40.00 per hundred for bullets of this quality. These are not seconds or blems — the are quality Nosler-made bullets produced for Midsouth’s Match Monster bulk sales program.
4. Sportsman’s Guide — Frankford Arsenal Case Tumbler Kit
For just $69.99, this Frankford Arsenal Kit provides everything you need to clean brass: Vibratory Tumbler, Rotary Media Separator, Bucket, Corn Cob Media (3 lbs.), and Brass Polish. The Case Tumbler holds up to 600 9mm cases or 350 .223 Rem cases. The separator system is generous, with a 3.5-gallon bucket. NOTE: Sportsman’s Guide Buyers Club members can purchase for $62.99.
5. CDNN Sports — Ruger American Ranch Rifle (Tan), $389.99
Here’s a nice little varmint rifle from Ruger with some nice features at a very attractive price, $389.99. This .223 Rem rifle features a 16.5″ hammer-forged barrel barrel threaded 1/2″-28 at the muzzle for brake or suppressor. The action, which features a 70° three-lug bolt, and Picatinny-style scope rail, sits in an aluminum bedding block. The crisp trigger adjusts down to 3 pounds. With a weight (before optics) of 6.1 pounds, this is a handy carry-around varminter.
6. MidwayUSA — Padded Scoped Rifle Case, $24.99
This 48″-long, thickly-padded gun case will hold most tactical-style rifles and hunting rifles. At a fraction of the cost of a big, cumbersome drag bag, this case may be all you need. The heavy duty padding is over 1″ thick on both sides to protect your rifle and optics investment from rough handling. A large pocket will hold a couple boxes of ammo and other accessories. We like this bag much better than the typical gun-store soft cases. It offers much better padding and more room for large scopes. It is on sale this week at MidwayUSA for just $24.99 in four colors: black, tan, OD green, and gray. In addition to the 48″ case shown, 40″ and 44″ versions are available.
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Field Target (FT) and Hunter Field Target (HFT) airgun disciplines are popular outdoor shooting sports that simulate the challenges of hunting small game. One of the unique aspects of FT competition is target range-finding using parallax and optical focus. (HFT is limited to lower power scopes, so this type of range-fiding is not used in HFT.) Range-finding is very important because the pellets shot by FT airguns drop rapidly once they leave the muzzle (pellets can drop roughly 5″ at 50 yards). If you don’t have your scope set to the correct distance, you’ll probably miss the target high or low.
FT competitors employ high-magnification (35-55X) scopes to sight targets placed from 10 to 55 yards (7.3 to 50m in the UK). Because these scopes have very short depth-of-field at high-magnification, the target will be out of focus unless you have the scope focus/parallax control set very precisely. But competitors can use this to their advantage — once the target is precisely focused, you have effectively established its distance from the shooter. FT scopes often have large-diameter wheels on the side parallax control so the focus can be set very precisely. You can then read marks placed on the scope to adjust the amount of elevation need to put the pellet on target.
To simplify the adjustment of elevation on FT rifles, competitors will place tapes on the windage knobs with marks that correspond to distances in 3-5 yard (or smaller) increments. These marks allow you to quickly spin your elevation to the setting matching the target range established with your focus/parallax control.
Field Target Accessories
There are a variety of specialized products for FT competitors that help you set up your scope for precise ranging. First, Compufoil offers a computer program, ScopeKnob, that lets you easily create accurate elevation knob tapes for your scope. ScopeKnob even comes with a built-in Ballistics Module that will calculate the pellet trajectory for you and plot range settings for your tape. Chairgun.com also offers ChairGunPRO, specialized airgun ballistics software that lets you simultaneously compare four different pellets, or different scope heights.
In the past, the A-Team offered replacement elevation knobs optimized for use with yardage marking tapes. These were offered in two versions, one which replaced the existing turret altogether and a second which clamped OVER the factory turret. Shown at right is the larger-diameter version in place over the factory turret. Unfortunately we don’t know a current source for this product, but this may help you crate something similar on your own.
Last but not least, Pyramid Air offers large-diameter parallax control wheels. According to Pyramid: “The enlarged sidewheel is the most popular FT scope accessory of all. It lets you put white artist’s tape around the rim to mark the actual distances at which the scope focuses”. A 6″ sidewheel provides over 18″ of space on which to inscribe yardage, and that means you can have a meaningful separation between 18 yards and 20 — where there is a huge parallax and trajectory difference. Though the ranges are already engraved on the rim of the wheel, field target competitors will measure them again on an actual range and write the markings on a strip of white artist’s tape.
Tips on Field Target Scope Set-Up
The creator’s of the A-Team knobs suggest taking your time when setting up a scope for Field Target competition: “We normally take from three to four hours preparing a scope to be mounted on a gun. We mark the scope in 1-yard increments from 9 to 40 yards, then to 55 yards by 3 or 5-yard increments depending on the scope being calibrated.”
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One of our Forum members complained that he wasn’t able to set his primers flush to the rim. He tried a variety of primer tools, yet no matter what he used, the primers still didn’t seat deep enough. He measured his primers, and they were the right thickness, but it seemed like his primer pockets just weren’t deep enough. He was mystified as to the cause of the problem.
Well, our friend Boyd Allen diagnosed the problem. It was the decapping rod. If the rod is adjusted too low (screwed in too far), the base of the full-diameter rod shaft (just above the pin) will contact the inside of the case. That shaft is steel whereas your case is brass, a softer, weaker metal. So, when you run the case up into the die, the shaft can actually stretch the base of the primer pocket outward. Most presses have enough leverage to do this. If you bell the base of the primer pocket outwards, you’ve essentially ruined your case, and there is no way a primer can seat correctly.
The fix is simple. Just make sure to adjust the decapping rod so that the base of the rod shaft does NOT bottom out on the inside of the case. The pin only needs to extend through the flash hole far enough to knock the primer out. The photo shows a Lyman Universal decapping die. But the same thing can happen with any die that has a decapping rod, such as bushing neck-sizing dies, and full-length sizing dies.
Whenever you use a die with a decapping pin for the first time, OR when you move the die to a different press, make sure to check the decapping rod length. And it’s a good idea, with full-length sizing dies, to always re-check the height setting when changing presses.
Lee Universal Decapping Die on SALE for $9.89
Speaking of decapping tools, MidwayUSA has the Lee Universal Decapping Die on sale this month (June, 2010), for just $9.89 (item 136543). There are many situations when you may want to remove primers from fired brass as a separate operation (prior to case sizing). For example, if your rifle brass is dirty, you may want to de-cap before sizing. Or, if you load on a progressive press, things will run much more smoothly if you decap you brass first, in a separate operation. The Lee Universal Decapping Die will work with cartridges from 17 Fireball all the way up to 45-70. However, NOTE that the decapping pin supplied with this Lee die is TOO LARGE for LAPUA 6.5×47, 6BR, 220 Russian, and Norma 6 PPC flash holes. Because the pin diameter is too large for these brass types, you must either turn down the pin, or decap with a different tool for cases with .059″ flash-holes. Otherwise, the Lee Decapping Die works well and it’s a bargain.
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With barrels, one wonders “Can a little more length provide a meaningful velocity gain?” To answer that question, Rifleshooter.com performed an interesting test, cutting a .308 Win barrel from 28″ all the way down to 16.5″. The cuts were made in one-inch intervals with a rotary saw. At each cut length, velocity was measured with a Magnetospeed chronograph. To make the test even more interesting, four different types of .308 Win factory ammunition were chronographed at each barrel length.
Test Barrel Lost 22.7 FPS Per Inch (.308 Win Chambering)
How much velocity do you think was lost, on average, for each 1″ reduction in barrel length? The answer may surprise you. With a barrel reduction from 28″ to 16.5″, the average speed loss of the four types of .308 ammo was 261 fps total. That works out to an average loss of 22.7 fps per inch. This chart shows velocity changes for all four ammo varieties:
Summary of Findings: The average velocity loss per inch, for all four ammo types combined, was 22.7 FPS. By ammo type, the average loss per inch was: 24.6 (Win 147 FMJ), 22.8 (IMI 150 FMJ), 20.9 (Fed GMM 168gr), and 22.5 (Win 180PP).
Interestingly, these numbers jive pretty well with estimates found in reloading manuals. The testers observed: “The Berger Reloading manual says for the 308 Winchester, ‘muzzle velocity will increase (or decrease) by approximately 20 fps per inch from a standard 24″ barrel’.”
How the Test Was Done
The testers described their procedure as follows: “Ballistic data was gathered using a Magnetospeed barrel mounted ballistic chronograph. At each barrel length, the rifle was fired from a front rest with rear bags, with five rounds of each type of ammunition. Average velocity and standard deviation were logged for each round. Since we would be gathering data on 52 different barrel length and ammunition combinations and would not be crowning the barrel after each cut, we decided to eliminate gathering data on group sizes. Once data was gathered for each cartridge at a given barrel length, the rifle was cleared and the bolt was removed. The barrel was cut off using a cold saw. The test protocol was repeated for the next length. Temperature was 47° F.”
CLICK HERE to Read the Rifleshooter.com Test. This includes detailed charts with inch-by-inch velocity numbers, multiple line charts, and complete data sets for each type of ammo. Rifleshooter.com also offers ballistics graphs showing trajectories with different barrel lengths. All in all, this was a very thorough test by the folks at RifleShooter.com.
Much Different Results with 6mmBR and a Longer Barrel
The results from Rifleshooter.com’s .308 barrel cut-down test are quite different than the results we recorded some years ago with a barrel chambered for the 6mmBR cartridge. When we cut our 6mmBR barrel down from 33″ to 28″, we only lost about 8 FPS per inch. Obviously this is a different cartridge type, but also our 6mmBR barrel end length was 5″ longer than Rifleshooter.com’s .308 Win start length. Velocity loss can be more extreme with shorter barrel lengths (and bigger cartridges). Powder burn rates can also make a difference.
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You probably know by now that David Tubb has introduced a new two-stage trigger for Remington 700 rifles, the Model T7T. Priced at $385.00, the new T7T Trigger is a true two-stage design: first and second stages are independently adjustable for both weight and feel. Overall (combined stage) trigger pull weight can be adjusted from just under 1 pound to slightly over 3.5 pounds.
If you are interested in the 7ZT, watch these two videos. The first shows how to adjust pull-weights for both stages. The second video shows how to modify your stock to provide clearance for the T7T.
This video shows how to adjust the new Tubb T7T two-stage trigger for Remington 700s:
The new T7T is a quality product. We’ve received good feedback from “early adopters” who tell us the two-stage function works well. While installation of the T7T may require minor modifications to your action, most gun owners with basic mechanical skills can install the T7T by themselves. The T7T is made using stainless steel and aluminum for maximum corrosion resistance. Note, installation of the T7T trigger (either Right-Hand or Left-Hand) also requires a companion T7T bolt release, offered by DavidTubb.com for $10.00.
This video shows how to modify your stock to fit the T7T trigger:
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